Control apparatus for internal combustion engine

A control apparatus for an internal combustion engine, the control apparatus comprising:

• a rotational speed parameter detection unit configured to detect a rotational speed parameter that represents a rotational speed of the internal combustion engine including a plurality of cylinders;
• a single misfire detection unit configured to detect a single misfire that is a misfire for every ignition for each of the plurality of cylinders, based on the rotational speed parameter that has been detected in each combustion stroke of the plurality of cylinders;
• a misfire counter configured to count, as a misfire counter value, the number of times that the single misfire has been detected for each of the plurality of cylinders;
• a misfire determination unit configured to determine whether the misfire is occurring in each of the plurality of cylinders, based on the misfire counter value;
• and
• an ignition timing correction unit configured to correct an ignition timing of the cylinder that has been determined that the misfire is occurring to an advance angle side, wherein
• the misfire determination unit determines that the counter value reaches a predetermined value, and
• the ignition timing correction unit corrects the ignition timing of the cylinder to the advance angle side by a predetermined amount Whenever the single misfire is detected, after the misfire counter value reaches the predetermined value,
• the internal combustion engine includes a catalyst for purifying exhaust gas,
• the misfire determination unit determines the misfire, while catalyst warm-up control for controlling the ignition timing to a retard angle side is being conducted to promote warm-up of the catalyst,
• the ignition timing correction unit corrects the ignition timing of the cylinder to the retard angle side by a predetermined amount until an advance angle correction amount for correcting the ignition timing to the advance angle side reaches the value 0, after it is determined that the catalyst warm-up control should be ended, and
• the catalyst warm-up control is ended when the advance angle correction amount reaches the value 0.